Most of conventional vision processing apparatuses in a robot system is restrictively used in recognizing an external circumstance of a robot through input information of only one camera. Therefore, there is a disadvantage that it is necessary to compositively use information obtained from other sensors such as a ultrasonic sensor, an infrared sensor, or the like, in order to make use of the conventional vision processing apparatuses for the travel and movement of the robot. In particular, because a necessary vision processing operation is performed in a robot server connected to a robot terminal over network in the network based intelligent service robot, there is also a disadvantage that it causes excessive communication traffics between the robot terminal and the robot server.
FIG. 1 is a block diagram illustrating a whole system of a general network based intelligent service robot. As illustrated in FIG. 1, the general network based intelligent service robot system includes a robot server 20 and a plurality of robot terminals 10: 1, 2, . . . , n interfaced with the robot server 20. Herein, each of the robot terminals 10 is configured with a robot vision processing unit 101 for acquiring and processing an external image, a robot control unit 102 for controlling the robot terminal 10, a robot server communication unit 103 for serving a role of communicating with the robot server 20, and a robot sensor and drive unit 104 for sensing various kinds of external circumstances and driving the robot terminal 10.
In order to drive the robot terminal 10 in the above system, the robot terminal 10 transmits acquired image information to the robot server 20, and the robot server 20 controls the travel of the robot after recognizing/processing images for obstacles to the robot's traveling and moving.
In the network based intelligent service robot system, since complex applications with high capacity and a load requiring high speed operation, which are difficult to be processed in each robot terminal 10, are concentrated on the robot server 20 connected over the network, it is possible to implement the robot terminal with a relative low cost. Accordingly, it is possible to provide users with various and high quality services with low price.
That is, in order to provide the users with various functional services with low price in the network based intelligent service robot, the robot controller 102 of the robot terminal 10 is implemented by using a low power embedded processor having advantages in an aspect of price and power consumption, instead of using a personal computer with high price, considering the robot terminal 10 to become cheap.
In addition, the robot controller 102 of the robot terminal 10 is implemented such that it has relatively low computing power.
Furthermore, in case of processing the complex applications in the robot server 20, although the robot terminal 10 may be implemented at low price relatively, communication traffic with the robot server 20 increases after all to raise the communication expense because lots of applications for executing the service are performed within the robot server 20. On the contrary, if various functions are performed in the robot terminal 10 for reducing the expense of the communication with the robot server 20, the load to be processed in the robot terminal 10 may increase so that the robot controller 102 should be implemented at high price for having high computing power.
Thus, there is a need to make a compromise with the constitution of the robot terminal 10 and the communication traffic with the robot server 20, when configuring the network based intelligent service robot system. In particular, the communication traffic between the robot server 20 and the robot terminal 10, becomes a factor which has a large effect on stability of the system as well as the communication expense because the plurality of the robot terminals 10 are connected to the one robot terminal 20 as illustrated in FIG. 1.
Therefore, in order that the network based intelligent service robot may provide the users with the various functional services with low price, the cost of the robot terminal should be reduced to be low, first. In addition, another consideration is the communication expense which is caused by using the network. That is, according to the prior art, there is a drawback that it should be considered the communication traffic between the robot terminal and the robot server in the network based intelligent service robot, which is a cause for a considerable additional expense due to the network communication.